Fix Anthropic 529 & 503 Overloaded Errors
Transient Server-Side Failure
Unlike 4xx errors (which indicate a bad request), 529 (Overloaded) and 503 (Service Unavailable) are server-side signals that Anthropic's infrastructure is under heavy load. These are common during peak usage of Claude 3.5 Sonnet.
When Anthropic servers are busy, they return a 529 status. If your OpenClaw session doesn't have a robust retry strategy, the agent will crash or hang.
Next Step
Fix now, then reduce repeat incidents
If this issue keeps coming back, validate your setup in Doctor first, then harden your config.
What the Errors Look Like
Solution 1: Enable Exponential Backoff
The most effective way to handle 529 errors is to wait and try again. OpenClaw allows you to configure specific retry logic for the Anthropic provider.
{
"providers": {
"anthropic": {
"retry": {
"maxAttempts": 5,
"initialDelayMs": 1000,
"maxDelayMs": 10000,
"useExponentialBackoff": true
}
}
}
}Solution 2: Increase Timeout for Long Generations
During high-load periods, Anthropic may take longer to start streaming. Increasing the requestTimeout can prevent premature client-side disconnects.
# Set global request timeout to 60 seconds openclaw config set providers.anthropic.requestTimeout 60000
Solution 3: Multi-Region Failover (Advanced)
If you are using Anthropic via **AWS Bedrock** or **Google Vertex AI**, you can configure failover between different regions (e.g., US-East-1 to US-West-2) when one region returns a 503.
Recommended Retry Values
- Max Attempts: 5 (covers 95% of transient spikes)
- Initial Delay: 1000ms (1 second)
- Backoff Multiplier: 2.0x
Check Anthropic Status
If retries still fail after 5 attempts, check the official Anthropic status page to see if there is a major outage.
Official Anthropic StatusStill getting errors?
If you are seeing 4xx errors instead of 529, check these guides:
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